ES2561714T3 - Wireless communication system, its base station and mobile phone station, communication synchronization management method and timer control program for them - Google Patents

Abstract

A base station (102) for communicating with at least one of the mobile telephone stations (101), the base station (102) comprising: a timer unit (115) that establishes a period for deciding whether a link signal upstream from a mobile telephone station (101) is synchronized; and a timer control unit (114) that is capable of determining the specific period for each of the mobile telephone stations (101) and notifying the period to the mobile telephone station (101) after the establishment or restoration of an RRC.

Description

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DESCRIPTION

Wireless communication system, its base station and mobile phone station, communication synchronization management method and timer control program for them

Technical sector

The present invention relates to a wireless communication system that manages synchronization through the use of a timing and, more particularly, to a wireless communication system, its base station and mobile telephone station, a control method of the synchronization of the communication and a timer control program for them, which allows the base station to adaptively control the timing of a transmission of an uplink signal from the mobile telephone station.

Background

In the Long Term Evolution (LTE) of 3GPP, it is considered to maintain orthogonality between base stations (UE - User Equipment - User Equipment, in English) by assigning an orthogonal radio resource to each mobile telephone station (UE) when transmitting and receiving data (a radio resource is an area defined uniquely by time and frequency; radio resources are established by dividing time and frequency into discontinuous areas for allocation to different stations of mobile telephony, so that a resource does not overlap between two mobile telephony stations).

During the transmission / reception of an uplink signal, to eliminate interference between mobile telephone stations (UE) within the cell of a base station (Node B) so that the uplink signals can be properly demodulated by the base station (Node B), it is essential that the reception timing of the base station of an uplink signal from each of a plurality of mobile telephone stations (UE) is within a guard interval called "Cyclic prefix (CP) (Cyclic Prefix)." At the same time, regardless of whether synchronization in the transmission / reception of data is actually being maintained, it is assumed that synchronization is guaranteed if a reception timing does not exceed a predetermined period of time (i.e., during the operation of a timer ). Based on this assumption, it is decided that a state in which a reception timing is within the period of the timer is a status considered synchronized (that is, a mobile telephone station is assumed to be synchronized on the uplink) , and a state in which a reception timer is not within the period of the timer (i.e., a timer expires) is decided to be a state considered to be out of sync (i.e., a mobile telephone station is assumed to be NOT synchronized on the uplink).

A mobile telephone station (UE) that has been determined to be in a state considered to be out of sync sends a Non-Synchronized RACH (Non-Synchronized Random Access CHannel), in which a plurality of Mobile telephone (UE) stations compete for and use common radio resources, before transmitting an uplink signal. The mobile telephone station then receives a timing advance (TA - Timing Advance) from the base station to adjust its transmission timing. According to the TA, the mobile telephone station adjusts its transmission timing and finally synchronizes the uplink signal (that is, the uplink signal is received within a CP at the base station).

Since each mobile telephone station (UE) must ensure synchronization while transmitting an uplink signal, a timing advance (TA) is notified from the base station to each mobile telephone station, either at constant intervals or activated due to the occurrence of a specific event (for example, a rapid change in the travel speed of the mobile telephone station). The reference time period from when the timing advance (TA) has been updated for the last time until the mobile telephone station decides that it has returned to a desynchronized state is notified from the base station in the system information as the specific value for a cell, or is predefined as a fixed value. The reference time is monitored at the base station and at each of the mobile telephony (UE) stations through the use of a timer. When the timer expires (that is, when the reference time period described above expires), the mobile telephone station (UE) decides that it has passed from a state considered synchronized to a state considered synchronized.

In order to decide whether a mobile telephone station (UE) is in a state considered synchronized or in a state considered synchronized, the base station controls as many timers as the number of mobile telephone stations (UE) under its management. The order timer m supported by the base station (where m is an integer between 1 and M, and M is a natural number indicating the number of mobile telephone stations (UE) managed by the base station) corresponds to the timer supported by the mobile telephone station) (UE) of order m.

The plurality of timers controlled by the base station are configured with the same duration, and the same is true for the timers supported by the plurality of mobile telephone stations. The base station timers and mobile phone station timers are configured with a

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duration of timing that synchronization can be guaranteed by the mobile telephone station (UE) that is traveling at the maximum speed (for example, 350 km / h) of all mobile telephone stations (UE) supported by the base station . The duration of the timer is therefore shorter than the minimum duration of the excess of time with which this mobile telephone station (UE) will go out of sync. A determination is made between a state considered out of sync and a state considered synchronized based solely on the state of the timer, regardless of the actual travel speed of the mobile telephone station (UE). Non-patent Literature 1 describes an example of a process for setting a transmission timing during the transfer of an uplink signal in the Long Term Evolution (LTE) of the 3GPP described above.

When data is generated for transmission to the base station, a mobile telephone station (UE) in a status considered synchronized first transmits a Planning Request (SR - Scheduling Request) to the base station to request a resource radio station on which to transmit the data, using a specific radio resource for the mobile telephone station (UE). One method that can be used to assign a specific radio resource to a mobile telephone station (UE) is to periodically assign a radio resource on which to transmit an SR to each of the mobile telephone (UE) stations that are in a status considered synchronized. On the other hand, when a mobile telephone station (UE) in a state considered to be out of sync transmits an SR, it first transmits an unsynchronized RACH and receives a timing advance (TA) to control the transmission timing and, at the same time , assigns a specific radio resource to the mobile telephone station (UE) on which to transmit the SR.

It is clear from the foregoing, that a mobile telephone station (UE) in a state considered to be out of sync suffers a longer latency (or delay due to waiting time) before it can initiate data transmission, than a telephone station mobile in a state considered synchronized. This is because the first mobile telephone station additionally requires a transmission stage of a non-synchronized RACH before being able to perform a transmission stage of an SR. In addition, since orthogonality between mobile telephone (UE) stations is not guaranteed for a non-synchronized RACH, a collision between mobile telephone (UE) stations may occur. If a collision occurs, the transmitted unsynchronized RACH may not be detected by the base station, in which case the mobile telephone (UE) station must retransmit an unsynchronized RACH. This further increases latency.

Non-patent literature 1 3GPP RAN WG2 Contribution [R2-063401.doc NTT DoCoMo]
http://www.3gpp.org/ftp/tsg_ranAA/G2_RL2/TSGR2_56/Documents/

Non-patent literature 2 3GPP RAN WG1 Contribution [R1-063377.doc Nokia]
http://www.3gpp.org/ftp/tsg_ran/WG1_RL1/TSGR1_47/Docs/

Non-patent literature 3 3GPP RAN WG1 Contribution [R1-063405.doc Siemens]
http://www.3gpp.org/ftp/tsg_ran/WG1_RL1/TSGR1_47/Docs/

In the related technique described above, the duration of the timer is set based on the time in which synchronization is guaranteed by a mobile telephony station (UE) that travels rapidly (for example, at a speed of 350 km / h) . This leads to a problem in which a mobile telephone station (UE) that is still or moving at low speed can be decided to be in a state considered to be out of sync when a timer expires, even if the actual uplink synchronization it stays.

In addition, if other data is produced at the mobile telephony station (UE) and an uplink signal must be transmitted during a period in which the timer has expired, but the synchronization really remains, the latency before the data can being transmitted increases even more.

This is because a static or slow-moving mobile telephone station (UE) decides that it is out of sync based on the timer, even if it is actually synchronized and can transmit a Planning Request (SR - Scheduling Request, in English) using a radio resource specifically assigned to it. In such a situation, the mobile telephone station first needs to transmit a non-synchronized RACH to receive a timing advance (TA) from the base station (Node B), so that it can be assigned to a radio resource over the which transmit the SR according to the timing advance (TA).

(Objects of the invention)

An object of the present invention is to provide a wireless communication system, its base station and mobile telephone station, a method of managing the synchronization of the communication and a timer control program for them, which can control the duration of the timer used to decide whether a mobile telephone station is in a state considered synchronized or in a state considered adaptively synchronized for each mobile telephone station, thereby minimizing the chances of a synchronized mobile telephone station being considered in a considered state out of sync

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Another object of the present invention is to provide a wireless communication system, its base station and mobile telephone station, a method of managing the synchronization of the communication and a timer control program for the same, which can reduce a latency in the transmission of an uplink signal during a period in which a mobile telephone station in a state considered to be out of sync is actually synchronized.

Summary

The invention relates to a wireless communication system, its base station and mobile telephone station, a method of controlling the base station and a method of controlling the mobile telephone station as set forth in the appended claims. .

The present application also describes a base station of a wireless communication system that performs wireless communication between a mobile telephone station and a base station, which comprises

a timer unit that establishes a period, during which the synchronization of a reception timing at the base station for an uplink signal from the mobile telephone station is guaranteed and, depending on the occurrence or non-occurrence of an expiration of the period, decides whether the mobile telephone station is in a state considered synchronized, in which synchronization of the uplink is guaranteed, or in a state considered out of sync, in which synchronization of the uplink is not guaranteed, and

a timer control unit that has been realized capable of determining the period of the timer unit for each mobile telephone station according to the state of the mobile telephone station and the update of the timer unit.

The present application also describes a mobile telephone station of a wireless communication system that performs wireless communication between a mobile telephone station and a base station, comprising

a timer unit that establishes a period, during which the synchronization of a reception timing at the base station for an uplink signal from the mobile telephone station is guaranteed and, depending on the occurrence or non-occurrence of an expiration of the period, decides whether the mobile telephone station is in a state considered synchronized, in which synchronization of the uplink is guaranteed, or in a state considered out of sync, in which synchronization of the uplink is not guaranteed, and

a timer control unit that has been realized capable of determining the duration of the timer according to the state of the mobile telephone station and the update of the timer unit.

The present application also describes a wireless communication system that performs a wireless communication between a mobile telephone station and a base station, comprising

the base station and the mobile phone station,

comprising a timer unit that establishes a period, during which the synchronization of reception timings at the base station for uplink signals from the mobile telephone station is guaranteed and, depending on the occurrence or non-occurrence of an expiration of the period, decides whether the mobile telephone station is in a state considered synchronized, in which synchronization of the uplink is guaranteed, or in a state considered unynchronized, in which synchronization of the uplink is not guaranteed, and

at least some of the base station and mobile phone station

it comprises a timer control unit that has been realized capable of determining the timer duration of at least some of the base station and the mobile telephone station adaptively for each mobile telephone station according to the state of the telephone station Mobile and timer unit update.

The present application also describes a method of synchronization management in the wireless communication system to effect a wireless communication between a mobile telephone station and a base station, comprising

at the base station and the mobile phone station,

have a timer stage of setting a period, during which the synchronization of a reception timing at the base station for an uplink signal from the mobile telephone station is guaranteed and, depending on the occurrence or non-occurrence of a expiration of a period, decide on the part of a timer if the mobile telephone station is in a state considered synchronized, in which the

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uplink synchronization is guaranteed, or in a state considered out of sync, in which uplink synchronization is not guaranteed, and

at least one of the base station and mobile phone station

determine the period used in the timer stage of at least one of the base station and the mobile telephone station adaptively for each mobile telephone station according to the state of the mobile telephone station and the timer update.

The present application also describes a timer control program that is performed by a computer of a wireless communication system that performs wireless communication between a mobile telephone station and a base station to operate at the base station,

making the computer run

a function to establish a period, during which the synchronization of a transmission timing at the base station for an uplink signal from the mobile telephone station is guaranteed and, depending on the occurrence or non-occurrence of a period expiration , decide on the part of the timer if the mobile telephone station is in a state considered synchronized, in which synchronization of the uplink is guaranteed, or in a state considered desynchronized, in which synchronization of the uplink is not guaranteed, and

a timer control function that is performed capable of determining the duration of the timer for each mobile telephone station, according to the state of the mobile telephone station and the timer update.

The present application also describes a timer control program that is performed by a computer of a wireless communication system that performs wireless communication between a mobile telephone station and a base station for operating in the mobile telephone station,

making the computer run

a function to establish a period, during which the synchronization of a reception timing at the base station for an uplink signal from the mobile telephone station is guaranteed and, depending on the occurrence or non-occurrence of a period expiration , decide on the part of the timer if the mobile telephone station is in a considered synchronized state, in which the uplink synchronization is guaranteed, or in a considered synchronized state, in which the uplink synchronization is not guaranteed, and

a timer control function that is capable of determining the duration of the timer for each mobile telephone station, according to the state of the mobile telephone station and the timer update.

An effect of the present invention is that it decreases the probability that a latency before data transmission increases when a mobile telephone station is actually synchronized is considered as synchronized based on an expiration of the timer used to decide whether a mobile telephone station it is in a state considered synchronized or in a state considered synchronized. This is because the present invention can control the duration of the timer of each mobile telephone station adaptively with respect to the travel speed of the mobile telephone station.

Brief description of the drawings

Fig. 1 is a block diagram for explaining a first exemplary embodiment of the present invention;

Fig. 2 is a block diagram for explaining the synchronization timer according to the first exemplary embodiment of the present invention;

Fig. 3 is a block diagram for explaining the adaptive control part of the timer according to the first exemplary embodiment of the present invention;

Fig. 4 is a block diagram for explaining the method of estimating the travel speed of a mobile telephone station;

Fig. 5 is a block diagram for explaining correlations between timing advance values for reception timing and transmission timing;

Fig. 6 is a diagram to explain the table that defines the correlations between travel speed and timer duration, based on what timer duration has been determined, according to the first exemplary embodiment of the present invention. ;

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a Fig. 7 is a diagram for explaining the method for determining a duration of crimer timer example embodiment of the present invention;

Fig. 8 is a diagram to explain the method for determining the duration of an example timer of the present invention;

Fig. 9 is a diagram for explaining the procedure for determining the duration of a timer according to the first exemplary embodiment of the present invention;

Fig. 10 is a block diagram for explaining the adaptive control part of a timer according to a first exemplary embodiment of the present invention;

Fig. 11 is a diagram to explain the table that defines the correlations between the timing advance and the duration of a timer, based on what timer duration has been determined, in accordance with the example example embodiment of the present invention;

Fig. 12 is a diagram for explaining the method for determining the duration of a timer according to the first exemplary embodiment of the present invention;

Fig. 13 is a diagram for explaining the method for determining the duration of a timer according to the first exemplary embodiment of the present invention;

Fig. 14 is a block diagram for explaining the adaptive control part of a timer according to a first exemplary embodiment of the present invention;

Fig. 15 is a flow chart showing the operation of the base station according to the exemplary embodiment of the present invention;

Fig. 16 is a flow chart showing the operation of the base station according to the exemplary embodiment of the present invention;

Fig. 17 is a flow chart showing the operation of the base station according to the exemplary embodiment of the present invention;

Fig. 18 is a block diagram showing a hardware structure of the mobile telephone station and the base station according to the first exemplary embodiment of the present invention;

Fig. 19 is a block diagram for explaining a second exemplary embodiment of the present invention;

Fig. 20 is a block diagram for explaining the adaptive control part of a timer according to a second exemplary embodiment of the present invention;

Fig. 21 is a block diagram for explaining the adaptive control part of a timer according to a second exemplary embodiment of the present invention;

Fig. 22 is a block diagram for explaining the adaptive control part of a timer according to a second exemplary embodiment of the present invention;

Fig. 23 is a diagram to explain the procedure for determining the duration of a timer according to the second exemplary embodiment of the present invention;

Fig. 24 is a block diagram for explaining an exemplary embodiment of the present invention;

Fig. 25 is a block diagram for explaining the adaptive control part of a timer according to a third exemplary embodiment of the present invention;

Fig. 26 is a diagram for explaining the procedure for determining the duration of a timer according to the third exemplary embodiment of the present invention;

Fig. 27 is a block diagram for explaining a fourth exemplary embodiment of the present invention;

Fig. 28 is a block diagram for explaining the adaptive control part of a timer according to a fourth exemplary embodiment of the present invention;

Fig. 29 is a diagram to explain the procedure for determining the duration of a timer according to the fourth exemplary embodiment of the present invention;

Fig. 30 is a block diagram showing the system structure of a wireless communication system according to a fifth exemplary embodiment of the present invention;

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agreement with the agreement with the

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Fig. 31 is a block diagram showing the system structure of a wireless communication system according to a sixth exemplary embodiment of the present invention;

Fig. 32 is a block diagram showing the system structure of a wireless communication system according to a seventh exemplary embodiment of the present invention;

Fig. 33 is a diagram illustrating a schematic concept of a wireless communication system according to an eighth exemplary embodiment of the present invention;

Fig. 34 is a diagram illustrating a schematic concept of a wireless communication system in accordance with a ninth exemplary embodiment of the present invention;

Fig. 35 is a diagram illustrating a schematic concept of an example communication system according to a tenth exemplary embodiment of the present invention.

Example Execution

The present invention will now be described in detail with reference to the drawings.

First, in the exemplary embodiments of the present invention, an initial value Ttmo for the timer, which is used to decide whether a mobile telephone station is in a state considered synchronized or in a state considered synchronized, is established during a period in which which the synchronization of a rapidly moving mobile telephone station can be guaranteed. This can be done using a method similar to the commonly used methods. In 3GPP LTE, a travel speed of 350 [km / h] is assumed as the travel speed to set the duration of a timer.

In Non-Patent Literature 2, the tolerance for deviations in transmission timing required for an uplink signal to be detected correctly is estimated at approximately 1 [ps]. In Non-Patent Literature 3, the worst case for loss of synchronization is assumed to be when synchronization is lost as a result of a deviation of 1 [ps] in transmission timing.

Using these values as a reference, each exemplary embodiment uses approximately 1.5 [s] as the initial value of Tmo for the timer. This is the length of time that causes the transmission timing to deviate by 1 [ps] at a travel speed of 350 [km / h]. The timer duration set in the first timer of order m (first timer #m) supported by the base station (Node B) and the timer duration set in the second timer by the mobile phone station of order m (UE # m) are equal, where m is an integer between 1 and M, and M is a natural number that represents the number of mobile telephone stations under the management of the mobile telephone station. A random access signal transmitted by a mobile telephone station in a desynchronized state consists of a randomly selected sequence of a predetermined number of sequences (for example, the Zadoff-Chu sequence).

"Synchronization" as used herein refers to a state in which a transmission timing is controlled by the base station, such that a reception timing in which an uplink signal is transmitted from the station Mobile telephony to the base station is within the required accuracy. The reception timing varies depending on factors such as the distance between the mobile telephone station and the base station, that is, the position of the mobile telephone station. Therefore, a higher travel speed of the mobile telephone station results in a greater variation in the reception timing and, consequently, in a shorter duration of time during which the "synchronization" is maintained.

A distinction between a "considered synchronized state" and a "considered synchronized state" is decided on the basis of whether the timer is running or has expired. A "considered synchronized state" is a state in which the timer is running and, based on this fact, it is decided that uplink synchronization between the mobile telephone station and the base station can be guaranteed. A "status considered as out of sync" is a state in which the timer has expired and, based on this fact, it is decided that the uplink synchronization between the mobile telephone station and the base station cannot be guaranteed. This means that, even when a mobile phone station decides that it is in a “state considered out of sync,” it can actually be synchronized. On the contrary, even when a mobile telephone station decides that it is in a “considered synchronized state”, it may actually be out of sync.

Although the exemplary embodiments that follow are described with respect to the 3GPP LTE as an example, the purpose of the present invention is not limited to the LTE, but can be a wireless LAN, WiMAX or other similar technology. The present invention can be applied to any system that requires synchronous TDM-based connection and in which a deviation between transmission and reception timings can occur.

(First example embodiment)

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Fig. 1 is a block diagram showing the system structure of a wireless communication system according to the first exemplary embodiment of the present invention. In this exemplary embodiment, the calculation of an indicator value for the determination of the duration of a timer as well as the determination of the duration of the first timer supported by the base station and the second timer supported by the mobile telephone station ( UE), are made by the base station.

With reference to Fig. 1, the mobile telephone station (UE) 101 comprises a determination part 103, a basic signal generation part 104, an uplink signal generation part 105, an information input part transmission 106, a signal transmission part 107, a second timer 108 and a downlink signal demodulation part 109.

At the mobile telephone station (UE #m) 101, the demodulation part of the downlink signal 109 receives from the base station (Node B) 102 a downlink reception signal Sdltx containing a timing advance ( TA) for an uplink transmission timing, and produces the timing advance (TA) reproduced Srja, which corresponds to the timing advance (TA) received at the mobile telephone station; the timer control information Sjci, which notifies a reset of the second timer when a timing advance (TA) is notified from the base station (Node B); and Srtui reproduced timer update information, which corresponds to the timer update information indicative of a new timer duration in case the second timer has been updated.

The second timer 108 operates according to the control information of the Stci timer and the update information of the reproduced timer Srtui. When the Srtui reproduced timer update information is entered, the second timer 108 updates the duration of the second timer, and produces as status information if the information of whether the mobile telephone station (UE) #m is in a status considered synchronized or in a state considered out of sync. The second timer 108 can carry out the process to produce status information Sg such that, for example, it produces status information Ssi only when the mobile telephone station is in a state considered to be out of sync and does not produce status information Sg when The mobile phone station is in a state considered synchronized.

When the Sinfo transmission information to be transmitted to the base station (Node B) 102 is entered, the determination part 103 switches the connection according to the Status Information Ssi. More specifically, it switches the connection to the uplink signal generation part 105 if the Information indicates a status considered synchronized or to the basic signal generation part 104 if the Information indicates a state considered to be out of sync.

The basic signal generation part 104 has a function to generate and produce a basic signal for use in communicating with the base station (Node B) 102. In the example used in this and in the other example embodiments that are described below, a random access signal Srs is generated and produced in order to receive a timing advance (TA) from the base station (Node B) for synchronization of an uplink signal.

The uplink signal generation portion 105 adjusts the transmission timing to the timing advance (TA) reproduced Miss, and generates and produces an uplink signal Sus containing the Symph Transmission Information.

As the uplink transmission signal Sultx, the transmission signal portion 107 transmits the uplink signal Sus if the mobile telephone station is in a considered synchronized state, or the random access signal Srs if the mobile telephone station is in a state considered out of sync.

Referring to Fig. 1, the base station (Node B) 102 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 112, a timing calculation part 113, an adaptive timer control part 114, a synchronization timer 115, in which a synchronization timer may otherwise be referred to as a time alignment timer, and a downlink receiving portion 116.

At the base station (Node B) 102, the determination part 110 switches the connection according to the Status Information Ssi, which indicates the status of the mobile telephone station (UE) #m. More specifically, it switches the connection to the uplink signal demodulation part 112 if the information indicates a status considered synchronized, or to the basic signal demodulation part 111 if the information indicates a state considered to be synchronized.

The basic signal demodulation part 111 receives an input from a received uplink signal Sultx, which corresponds to a basic signal, and has a function to demodulate and produce the received uplink received signal Sultx- In the example used in this and in other exemplary embodiments described below, the basic signal demodulation portion 111 receives as input a received uplink signal Sultx corresponding to a random access signal Srs, and produces as information of

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random access detection Srdi the information indicating a sequence that exceeds the predefined detection threshold.

The uplink signal demodulation portion 112 demodulates a received uplink signal Sultx, which corresponds to an uplink signal Sus, and produces reproduced transmitted information Srinfo, which corresponds to the transmission information Symph-

The timing calculation part 113 has a calculation part of TA 1131 and a storage part of TA 1132. The timing calculation part 113 uses the calculation part of TA 1131 to detect the reception timing (i.e., a deviation in reception timing) for a received uplink signal Sultx, and calculates a timing advance (TA) STa to inform the mobile telephone station (UE) #m based on the reception timing detected. It then stores the resulting TA in the warehouse part of TA 1132 and produces this TA STa-

The adaptive control part of the timer 114, using as input the two or one of the received uplink signal Sultx and / or a timing advance (TA) Sta, determines the duration of the first timer #m and the second timer of the station of mobile telephony (EU) #m. It then produces the resulting timer duration as Stui timer update information, as well as the information that notifies a restart of the first timer #m by sending a timing advance (TA) to the mobile telephone station (UE) # m as timer control information Stci-

Synchronization timer 115, which has M first timers, operates in accordance with the update information of the STui timer and with the control information of the Stci timer, and produces status information if the information of the mobile telephone station ( UE) #m is in a state considered synchronized or a state considered synchronized.

The downlink transmission part 116, according to the status information Ssi, generates and transmits a downlink transmission signal Sdltx- The downlink transmission signal Sdltx contains a timing advance (TA) Sta and information of Stui timer update, in the case of a status considered synchronized, or contains a Sta timing advance (TA), Stui timer update information, and Srdi random access detection information in the case of a status deemed out of sync.

The synchronization timer consists of M first timers 117, as shown in Fig. 2. The first timer #m corresponds to the second timer of the mobile telephone station (UE) #m.

When the duration of the first timer #my and the second timer of the mobile telephone station (UE) #m is determined, the adaptive control part of the timer 114 uses as the indicator, both or some of a travel speed Svi, which is the result obtained by estimating the travel speed of the mobile telephone station (UE) # m and / or the variation information of the Stadi transmission timing, which is the result obtained by calculating a time variation for the timing advance (TA)

Figs. 3, 10 and 14 show the structure of the adaptive control part of the timer when a travel speed is used as an indicator; a time variation in the timing advance (TA); or a travel speed and a time variation in a timing advance (TA), respectively.

The adaptive control part of the timer 114 of Fig. 3 comprises a speed estimation part 118, which estimates the travel speed Svi of the mobile telephone station (UE) #m using as input an uplink received signal Sultx , and a timer determination portion 121, which determines, using the travel speed Svi as input, the duration of the first timer #m and the duration of the second timer of the mobile telephone station (UE) #m.

An estimation method for a travel speed that can be used here is to estimate it from a Doppler frequency Fd [Hz] (in which Fd is a real number greater than or equal to 0).

A Doppler frequency Fd can be estimated using the amount of phase rotation 0 [rad] (where 0 is a real number greater than or equal to 0) of a known pilot symbol. For example, as shown in Fig. 4, when it is assumed that Pi and P2 are vectors of received signal corresponding to the first and second pilot symbols, respectively, and that Tp is a time domain interval between P1 and P2 , an amount of phase 0 rotation can be obtained from a relational expression: 0 = {eos'1 (P1 • P2)} / Tp (where • it is an internal product). Using the value of 0 thus obtained, a Doppler frequency Fd can be obtained from the relational expression: Fd = 0 / {2ttTp}. In addition, using the Doppler frequency Fd thus obtained, a displacement speed can be calculated from the relational expression: v = Fd A = Fd (c / f), in which A is a wavelength [m], c is the speed of light, 3 x 108 [m / s] and f is a carrier frequency [Hz].

Fig. 5 shows an example correlation between a reception timing detected by the base station (Node B) and a timing advance (TA) so that a transmission timing is notified to the mobile telephone station (UE).

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In Fig. 5, a cyclic prefix (CP) is added to the header of an uplink signal (1 frame). The ideal reception time is such that the header of the CP reaches the header of each time interval. A deviation x [ps] of the reception time actually detected from the ideal reception timing occurs due to factors such as the movement of the mobile telephone station (UE) and the deviation in a transmission timing.

The amount of deviation in a transmission timing can be notified to the mobile telephone station (UE) using either of the following two methods: one method is to notify the absolute value of x [ps] as timing advance (TA); and another is to notify a value obtained by time division of x [ps] as timing advance (TA). In the method for notifying a time division value, it is notified that a transmission of the timing advance (TA) will be advanced or delayed in units of y [ps] of a predefined constant stage. Thus, in the case of the method for notifying a value per time division, a transmission timing can be transmitted using 1 bit to notify, for example, that the fixed value will be advanced by y [ps] if the value transmitted is 0, or the fixed value will be delayed at y [ps] if the transmitted value is 1. In this case, if the amount of deviation in a calculated transmission timing is actually +4 xy [ps], a value of 0 is transmitted four times, so that the transmission timing will advance by 4 xy [ps] in total.

There is another method that combines these two methods. A possible combination is to use the method to notify an absolute value when an initial value is established for a transmission timing, and the method to notify a value by time division when the transmission timing is updated.

Figs. 6 to 8 are diagrams to explain the method for determining and updating the duration of the first and second timers according to the first example embodiment.

The adaptive timer control part 114 is assumed to comprise a speed estimation part 118 and a timer determination part 121 (Fig. 3). The timer determination portion 121 determines the duration of the first and second timers, based on the travel speed Svi and the table that predefines the correlations between travel speed and timer duration. This exemplary embodiment uses the table shown in Fig. 6, which defines correlations between travel speed and timer duration.

Each of the timer durations in the table of Fig. 6 has been calculated using the following expression (1), and indicates the deviation time [s] caused for each travel speed at the same transmission timing value as the transmission timing value that is supposed to deviate by 1.5 [s] for a travel speed of 350 [km / h], which is the reference speed used when the initial value is set.

in which Dta [ps] is the deviation value in the transmission timing; v [km / h] is the travel speed of the mobile telephone station (UE); t [s] is the time caused by the deviation of Dta; and 6.7 [ps / km] is the Round Trip Delay (RTD), which is a propagation delay caused between the base station (Node B) and the mobile telephone station ( EU).

The expression (1) is used to create a table like the one shown in Fig. 6. The table has been created by first determining the threshold increments for the travel speed v and the amount of transmission timing deviation Dta acceptable, and then substituting the resulting values to calculate t in the expression (1). The value of t thus obtained is used as the duration of the timer.

In this exemplary embodiment, the speed estimation portion 118 of the base station (Node B) estimates the travel speeds of the two mobile telephony stations (UE # 1, UE # 2) at regular time intervals such as is shown in Fig. 7. The timer determination part 121 determines the duration of the first and second timers in each of the times to, ti, h, Í3). Based on the results, the first and second timers are adaptively controlled. It is assumed herein that the Initial Ttmo value for all pairs of the first and second timers is 1.5 [s], which is the duration of time determined for a travel speed of 350 [km / h].

In Fig. 7, mobile telephone station (UE) # 1 will be considered first. The travel speed in to is 40 [km / h]. This is much lower than the target travel speed 350 [km / h] for the initial value of all first and second pairs of timers, which implies that synchronization will continue for a longer period of time. In this case, the duration of the first timer # 1 and the second timer of the mobile telephone station (UE) # 1 may increase.

(Expression 1)

image 1

one

image2

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In reference to the Flg table. 6, the travel speed of 40 [km / h] is between 30 [km / h] and 120 [km / h], so that the duration of the first timer # 1 and the second timer of the mobile telephone station ( UE) # 1 is determined to be 4.5 [s].

The base station (Node B) notifies the mobile telephone station (UE) # 1 of the timer update information indicating that the timing advance (TA) and the duration of the second timer will be updated to 4.5 [s ]. Immediately after the issuance of this information, it updates the duration of the first timer # 1 to 4.5 [s] and causes the first timer # 1 to start operating again.

The mobile telephone station (UE) # 1 demodulates the downlink signal to reproduce the timing advance (TA) and the timer update information, updates the duration of the second timer to 2.9 [s] and causes the Second timer start operating again.

Similarly, the durations of the first timer # 1 and the second timer of the mobile telephone station (UE) # 1 at t = ti, t2, faith are determined to be 17.9 [s], 4.5 [ s] and 1.5 [s], respectively. Each time the timer duration is updated, the base station (Node B) notifies the mobile telephone station (UE) # 1 of the new duration of the second timer so determined.

Next, mobile telephone station (UE) # 2 will be considered. Its initial value is the same as the mobile telephone station (UE) # 1, that is, 1.5 [s]. The travel speed in to is 4 [km / h]. This speed is even lower than mobile telephone station (UE) # 1. The timer duration may increase because the synchronization will continue for a period of time longer than the mobile telephone station (UE) # 1.

Referring to the table in Fig. 6, the travel speed of 4 [km / h] is between 0 [km / h] and 5 [km / h], so that the duration of the first timer # 2 and the The second timer of the mobile telephone station (UE) # 2 is determined to be 107.5 [s].

The base station (Node B) notifies the mobile telephone station (UE) # 2 of the timer update information indicating that the timing advance (TA) and the duration of the second timer will be updated to 107.5 [s ]. Immediately after the issuance of this information, it updates the duration of the first timer # 2 to 107.5 [s] and causes the first timer # 1 to start operating again.

The mobile telephone station (UE) # 2 demodulates the downlink signal to reproduce the timing advance (TA) and the timer update information, updates the duration of the second timer to 107.5 [s] and causes the Second timer start operating again.

Similarly, the estimation of travel speeds at t = ti, t2, t3 results in 3 [km / h], 2 [km / h] and 2 [km / h], which are almost equal to the result for to. Therefore, it is determined that the timer setting in the observation period of Fig. 7 remains equal to 107.5 [s] without the need for any updating. The base station (Node B) and the mobile telephone station (UE) # 2 respectively repeat the process to reset the duration of the first timer # 2 or the second timer, and causing the respective timers to start operating again, each Once the timing advance (TA) is calculated and notified.

Fig. 8 shows the results of the timer duration determination as described.

previously.

Fig. 9 is a diagram showing the part of the process carried out by the base station (Node B) and the mobile telephone station (UE) #m according to this example embodiment, which refers to the determination of the duration of the first timer #my and the second timer of the mobile telephone station (UE) #m.

After receiving an uplink signal 1 from the mobile telephone station (UE) #m, the base station (Node B) calculates a timing advance (TA), estimates the travel speed and determines the duration of the first timer # m and the second timer of the mobile telephone station (UE) #m. The base station (Node B) then notifies the mobile telephony station (UE) #m of the timing advance (TA) and the updated duration of the second timer via a downlink signal 1. Immediately after transmitting the Downlink signal 1 to the mobile telephone station (UE) #m, the base station (Node B) resets the first timer #my and causes the first timer #m to start operating again.

The mobile telephone station (UE) #m demodulates the downlink signal 1 to reproduce the timing advance (TA) and the updated duration of the second timer. After updating the second timer to the duration of the timer played, the mobile telephone station (UE) #m restarts the second timer and causes the second timer to start operating again. The mobile telephone station (UE) #m then adjusts the transmission timing according to the timing advance (TA) reproduced and transmits an uplink signal 2.

A possible signal that can be used by the speed estimation part of the base station (Node B) for the estimation of a travel speed is a known signal (Reference signal: RS - Signal Reference) for the demodulation of mobile phone station (UE) data transmitted through

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of the Uplink Shared Channel (UL-SCH - UpLink-Shared CHannel), and including the uplink signal Control Information, or an RS for CQI measurement that is transmitted to allow the base station ( Node B) measure the quality of an uplink line (Channel Quality Indicator: CQI - Channel Quallty Indlcator, in English) transmitted through an UL-SCH. Likewise, a possible signal to notify the update of a timer is a signal for the control of Layer 1 / Layer 2 (L1 / L2 control signaling) transmitted through a Shared Downlink Channel (DL-SCH - DownLink - Shared Channel, in English, or a signal for data transmission (Physical Downlink Shared Channel: PDSCH - Physical Downlink Shared CHannel, in English) transmitted through a DL-SCH.

The adaptive control part of the timer 114 of Fig. 10 comprises a variation calculation part 119, which calculates and produces the time variation Sjadi in the timing advance (TA) to use a timing advance (TA) STA as input, and a timer determination part 122 which determines, using as input the variation of the Stadi time in the timing advance (TA), the duration of the first timer #m and the duration of the second timer of the mobile telephone station (EU) #m.

In the method according to the present invention that uses a time variation in a timing advance (TA) as an indicator for the determination of the duration of a timer, if an absolute value of the amount of deviation in the timing of a transmission is notified as timing advance (TA), the amount of variation in a timing advance (TA) in an observation period is used directly as a time variation in the timing advance (TA). On the other hand, if a value divided by the amount of deviation in a transmission timing is notified as timing advance (TA), the values divided by the timing of the timing advance (TA) are added to reproduce the amount actual deviation in the transmission timing, and the amount of variation of the transmitted timing reproduced in an observation period is used as time variation in the timing advance (TA).

The timer determination portion 122 determines the duration of the first and second timers, based on the time variation in the timing advance (TA) and the table that predefines the correlations between the time variation in the timing advance ( TA) and the duration of the timer. In the description of this exemplary embodiment, the method for notifying the amount of deviation in the timing advance (TA) as an absolute value will be considered.

Each of the timer durations in the table in Fig. 11 has been calculated using the following expressions (2) to (4), based on different correlations between an amount of deviation in the transmission timing during an observation interval and a travel speed at which such amount of deviation is expected to occur.

(Expression 2)

Dr, you] = v \ km!} {\ Y. —-— xi [s] x 6.7 [pis / km]

3600

•(2)

(Expression 3)

/ /?] = ^ x —x Acf [| iS]

6.7 [| is / km] Ar [s]

■ (3.)

(Expression 4)

Dm fos] = t [s] X —'¡‘I1- -. (4)

3: 4 Ai [s]

in which, in expression (2), Dta [ps] is the deviation value in the transmission timing; v [km / h] is the travel speed of the mobile telephone station (UE); t [s] is the time that causes a deviation of Dta; and 6.7 [ps / km] is the Round Trip Delay (RTD), which is a propagation delay caused between the base station (Node B) and the mobile telephone station (UE). In expression (3), Ad [ps] is the amount of deviation in the transmission timing caused in a period of At [s].

Assume that the variation calculation part of the base station (Node B) calculates a time variation in a timing advance (TA) at regular time intervals, that is, every 10 [s], for a telephone station mobile (UE) # 1, and that the results are those shown in Fig. 12. At each of the times (to, ti, t2, Í3), the timer determining part determines the duration of the timers first and second and controls the first and second timers adaptively. It is assumed herein that the Initial Thymus value for the first and second timers is 1.5 [s], which is the duration of time determined for a travel speed of 350 [km / h].

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The time variation in the timing advance (TA) in to calculated by the variation calculation part of the base station (Node B) is 2.18 [pis / 1 Os]. With reference to the table in Fig. 11, the variation is between 0.56 [pee / 1 Os] and 2.23 [ps / 10s], so that the duration of the timer can increase with respect to the nested value of 1.5 [s]. Based on the table, the duration of the first and second # 1 timers is determined to be 4.5

[s].

The base station (Node B) notifies the mobile telephone station (UE) # 1 of the timer update information Indicating that the timing advance (TA) and the duration of the second timer will be updated to 4.5 [s ]. Immediately after issuing this notification, it updates the duration of the first timer # 1 to 4.5 [s], and causes the first timer # 1 to start operating again.

The mobile telephone station (UE) # 1 demodulates the downlink signal to reproduce the timing advance (TA) and the timer update information, updates the duration of the second timer to 2.9 [s] and causes the Second timer start operating again.

Similarly, in t = ti, t2, t3, the results obtained by the base station (Node B) from the calculation of the time variation in the timing advance (TA) are 1.45 [ps / 10s], 1.92 [ps / 10s] and 3.28 [ps / 10s]. With reference to the table in Fig. 11, it can be determined that the durations of the first and second timers are 4.5 [s], 4.5 [s] and 1.5 [s], respectively.

Fig. 13 shows the results of the timer duration determination as described above.

The adaptive control part of the timer 114 of Fig. 14 comprises a speed estimation part 118, which estimates the travel speed SVi of the mobile telephone station (UE) #m using as input a received uplink signal Sultx ; a variation calculation part 119, which calculates and produces the Stadi time variation in the timing advance (TA) using as input a timing advance (TA) STA; and a timer determination part 120, which determines the duration of the first timer #m and the duration of the second timer of the mobile telephone station (UE) #m using as input the travel speed Svi and the time variation Stadi in the timing advance (TA). The adaptive control part of the timer 114 determines the duration of the first timer #m and the second timer of the mobile telephone station (UE) #m, using the method explained with reference to Figs. 3 and 10. In the case that both the Svi travel speed and the Stadi time variation in a timing advance (TA) are used as an indicator, it is desirable to use the smaller of the two timer durations obtained separately for the two indicators, but the largest can be used according to needs.

Next, the operation of a base station (Node B) according to this exemplary embodiment will be described.

Figs. 15 to 17 are flow charts showing the operation of the base station according to the exemplary embodiment of the present invention. Fig. 15 shows the operation in the case of a state considered to be out of sync. Fig. 16 shows the operation in the case of a status considered synchronized. Fig. 17 shows the operation to determine and update the duration of a timer.

With reference to Fig. 15, which refers to the case of a state considered to be out of sync, the base station (Node B) 102 initializes the first timer (T_SYNC = T) (step S101) and determines whether the basic signal (signal of random access) has been received or not (step S102).

The following assumptions are used in this memory.

First, the base station (Node B) 102 allocates a radio resource for the transmission of an uplink signal, such that an uplink signal (other than a random access signal) from the station of Mobile telephony (UE #m) 101 is always received before the timer expires. Therefore, a situation in which an uplink signal is received after a timer expiration never occurs.

Second, the duration (set value) of the first timer supported by the base station (Node B) 102 is the same as the duration of the second timer supported by the mobile telephone station (UE #m) 101.

Third, the calculation of a timing advance (TA) is carried out at regular intervals. It should be noted that the calculation at regular intervals is used as an example and that a timing advance (TA) can be calculated each time an uplink signal is received.

Fourth, a timing advance (TA) is transmitted to the mobile telephone station each time it is calculated. Since a threshold-based determination is not necessary, it is guaranteed that the next timing advance (TA) is calculated before expiration. However, if the base station (Node B) 102 has not received or transmitted any data for a certain fixed period of time and therefore no longer needs to maintain synchronization, it returns the information relating to the mobile telephone station to a state considered

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desynchronized when the expiration occurs, without instructing the mobile telephone station to transmit an uplink signal for the calculation of a timing advance (TA).

Although the present invention also allows a determination and updating of the duration of a timer to be carried out at regular time intervals (or in response to a certain activation event) (which similarly applies to the other example embodiments described below), this exemplary embodiment is described only with respect to the selection part that selects whether or not a timer duration will be determined.

If it determines that a basic signal (random access signal) has been received, the base station (Node B) 102 calculates a timing advance (TA) (step S103) and stores the calculated timing advance (TA) (step S104 ); transmits the timing advance (TA) to the mobile telephone station (UE #m) 101 (step S105); and causes the first timer to start operating (step S106). On the other hand, if it determines that a basic signal (random access signal) has not been received, the base station (Node B) 102 does not carry out the processes of steps S103 to S106.

As shown in Fig. 16, in the case of a status considered synchronized, the base station (Node B) 102 determines whether the T_SYNC value of the first timer is 0 or not (step S101). If the value is 0, the base station (Node B) 102 ends the process. Otherwise, it determines whether or not an uplink signal has been received (step S202).

If it determines that an uplink signal has been received, the base station (Node B) 102 determines whether or not to calculate a timing advance (TA) (step S203). Otherwise, the process ends.

If it determines that a timing advance (TA) must be calculated, the base station (Node B) 102 calculates a timing advance (TA) (step S204); stores the timing advance (TA) calculated in the storage part of TA 1132 (step S205); transmits the timing advance (TA) to the mobile telephone station (UE #m) 101 (step S206); reset the first timer (step S207); and starts the first timer (step S208). Otherwise, the base station (Node B) 102 does not carry out the processes of steps S204 to S208.

As shown in Fig. 17, the base station (Node B) 102 determines whether or not to update the first timer (step S301). If you determine that the first timer does not have to be updated, the process ends.

If it determines that the first timer must be updated, the base station (Node B) 102 calls the timing advance (TA) (step S302); calculates the rate of variation in the timing advance (TA) (step S303); determines the duration of the first timer T ’after the update (step S304); transmits the updated value T ’for the first timer to the mobile telephone station (UE #m) 101 (step S305); and updates the duration of the first timer to T ’(step S306).

Possible locations for inserting the operation of determining and updating the duration of a timer shown in Fig. 17 include, immediately after the conditional branch in step S202 carried out in the case of a condition considered synchronized in Fig. 16, or before the timer reset process in step S207. However, these locations are only examples and are not limited to these.

It is also possible to change the intervals at which to update a transmission timing from the mobile telephone station (UE #m), proportionally to a duration of the first and second timers determined for each mobile telephone station (UE #m).

An example hardware structure for the mobile phone station (UE #m) 101 and the base station (Node B) 102 will now be described.

Fig. 18 is a block diagram showing the hardware structure of the mobile telephone station 101 and the base station 102 in accordance with this exemplary embodiment of the present invention.

As shown in Fig. 18, the mobile telephone station 101 and the base station 102 according to the present invention can be made in any hardware structure similar to general computing devices, and mainly comprises a CPU (Process unit central - Central Processing Unit, in English) 1001; a main warehouse part 1002 which is a main memory, such as a RAM (Random Access Memory - Random Access Memory, in English), used as a data workspace and temporary data storage space; a communication part 1003, which transmits and receives data through the network 2000; a presentation part 1004, such as an LCD, printer and speakers; a data entry part 1005, such as a keyboard and a mouse; an interface part 1006, which is connected with peripherals to effect the transmission / reception of data; an auxiliary storage part 1007, which is a hard disk device consisting of a non-volatile memory, such as a ROM (Read Only Memory), a magnetic disk and a semiconductor memory; and a system bus 1008, which is connected between the aforementioned components of this information processing unit.

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It goes without saying that the operations of the mobile telephone station 101 and the base station 102 according to the present invention can be performed in the form of hardware, implementing a component in the mobile telephone station 101 and the base station 102 of circuit consisting of a LSI (Large Scale Integration, in English) or other hardware parts in which a program that performs these functions is incorporated, but these operations can also be performed in the form of software, causing the CPU 1001 in the process unit of the computer to execute a program that provides the functions of these components.

In other words, the CPU 1001 can perform the functions described above in a software-based mode by loading a program stored in the auxiliary warehouse part 1007 in the main warehouse part 1002, and executing the program to control the operations of the station. Mobile telephony 101 and base station 102.

The mobile telephone station and the base station in the example embodiments described below have a structure similar to those above, and the functions described above can be performed in a hardware-based or software-based mode.

(Effects of the first example embodiment)

As described above for the first exemplary embodiment, the present invention makes it possible for adaptive control of a timer to determine for each mobile telephone station (UE) whether it is in a state considered synchronized or in a state considered synchronized. This can reduce the likelihood of deciding that a truly synchronized mobile phone station is out of sync. In the case of LTE, it is also possible to reduce the likelihood that a latency before data transmission caused by the need for a truly synchronized mobile telephone station (UE) to transmit a synchronized RACH before transmitting a Planning Request.

(Second example embodiment)

Fig. 19 is a block diagram showing the system structure of a wireless communication system according to a second exemplary embodiment of the present invention. In this exemplary embodiment, the calculation of an indicator value to determine the duration of the first and second timers, as well as the determination of the duration of the first timer, are performed by the base station, and the determination of the duration of the Second timer is made by the mobile phone station.

With reference to Fig. 19, the mobile telephone station (UE) 201 comprises a determination part 103, a basic signal generation part 104, an uplink signal generation part 105, an information input part transmission 106, a signal transmission part 107, a downlink signal demodulation part 203, a timer determination part 204 and a second timer

205.

At the mobile telephone station (UE #m) 201, the downlink signal demodulation part 203 receives from the base station (Node B) 202 a downlink reception signal Sqltx, which contains a timing advance ( TA) for a transmission timing, and produces the timing advance (TA) reproduced SRTa, which corresponds to the timing advance (TA) received; STci timer control information, which notifies a restart of the second timer when a timing advance (TA) is notified from the base station (Node B); and a reproduced indicator value SR | D, which corresponds to the indicator used for the determination by the base station (Node B) of the duration of the first timer #m if the first timer #m is updated at the base station (Node B).

The timer determination part 204 determines the duration of the second timer using the reproduced indicator value SRid as input, and produces the result as update information of the Stuiu timer.

The second timer 205 operates in accordance with the Sjci timer control information and the Stuiu timer update information. When the Stuiu timer update information is entered, the second timer 205 updates the duration of the second timer, and produces as status information if the information of whether the mobile telephone station (UE) #m is in a state considered synchronized or in a state considered out of sync.

When the Sinfo transmission information is entered to be transmitted to the base station (Node B), the determination part 103 switches the connection according to the status information Sg. More specifically, it switches the connection to the uplink signal generation part 105 if the information indicates a status considered synchronized, or to the basic signal generation part 104 if the information indicates a status considered to be out of sync.

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The random access signal generation part 104 generates and produces a random access signal Srs, which is necessary to receive from the base station (Node B) a timing advance (TA) for synchronization of an uplink signal.

The uplink signal generation portion 105 adjusts the transmission timing according to the timing advance (TA) reproduced Miss, and generates and produces an uplink signal Sus which contains the Synthetic transmission information.

As the uplink transmission signal Sultx, the signal transmission portion 107 transmits the uplink signal Sus if the mobile telephone station is in a considered synchronized state, or the random access signal Srs if the mobile telephone station is in a state considered out of sync.

Referring to Fig. 19, the base station (Node B) 202 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 112, a timing calculation part 113, an adaptive timer control part 206, a synchronization timer 207 and a downlink transmission part 208.

At the base station (Node B) 202, the determination part 110 switches the connection according to the status information Ssi, which indicates the state of the mobile telephone station (UE) #m. More specifically, it switches the connection to the uplink signal demodulation part 112 if the information indicates a status considered synchronized, or to the basic signal demodulation part 111 if the information indicates a state considered to be synchronized.

The basic signal demodulation part 111 produces as random access detection information Srdi the information indicative of a sequence that exceeds the predefined detection threshold, using as input the received uplink signal Sultx corresponding to the random access signal SRS.

The uplink signal demodulation portion 112 demodulates a received uplink signal Sultx, which corresponds to an uplink signal Sus, and produces reproduced transmission information Srinfo, which corresponds to the Synthetic transmission information.

The timing calculation part 113 detects the reception timing of a received uplink signal Sultx and, based on the reception timing, calculates and produces the timing advance (TA) Sta to be notified to the mobile telephone station ( EU) #m.

The adaptive timer control portion 206, using as input the two or some of a received uplink signal Sultx and / or a timing advance (TA) Sta, calculates as Indicator Value Information Sid an Indicator to determine the duration of the first timer #my of the second timer of the mobile telephone station (UE) #m. Using the information of the value of the S | D Indicator, it determines the duration of the first timer #m as update information of the Stuin timer - The adaptive control part of the timer 206 then produces the information of the value of the resulting Indicator Sid, the Update Information of the resulting Stuin timer, as well as the Information notifying an update of the first timer #m by sending a timing advance (TA) to the mobile telephone station (UE) #m as timer control information Stci- The value information of the Sid indicator indicates the travel speed and the variation in transmission timing that has actually been used to determine the duration of the timer.

Synchronization timer 207, which has a number M of first timers, operates according to the update information of the Stuin timer and the control information of the Stci timer, and produces status information if the information of the telephone station mobile (UE) #m is in a state considered synchronized or in a state considered synchronized.

The downlink transmission part 208, in accordance with the Ssi Status Information, generates and transmits a downlink transmission signal Sdltx. The downlink transmission signal Sdltx contains a timing advance (TA) Sta and information of the Sid indicator value in the case of a status considered synchronized, or contains a timing advance (TA) STa, information of the Sid Indicator value and Srdi random access detection information in the case of a state considered unynchronized.

When the duration of the first timer #m is determined, the adaptive control part of the timer 206 uses as indicator two or some of a travel speed SVi, which is the result obtained by estimating the travel speed of the station mobile telephony (UE) #m, and / or Stadi transmission timing variation information, which is the result obtained by calculating a time variation in the timing advance (TA), and produces one or both of these, as applicable, as information of the Sid indicator value.

Figs. 20 to 22 show the structure of the adaptive timer control part when a travel speed and a time variation in a timing advance (TA) are used as an indicator; a travel speed; or a time variation in a timing advance (TA), respectively.

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The adaptive timer control portion 206 of Fig. 20 comprises a speed estimation part 209, which estimates the travel speed Svi of the mobile telephone station (UE) #m using as input data a signal received from link ascending Sultx; a variation calculation part 210, which calculates and produces the time variation Stadi in the timing advance (TA) using as input a timing advance (TA) STa; and a timer determination part 211, which determines the duration of the first timer #m using as input the travel speed Svi and the time variation Stadi in the timing advance (TA). The adaptive timer control portion 206 produces the travel speed Svi and the time variation Stadi in the timing advance (TA) as information of the indicator value Sid.

The adaptive timer control portion 206 of Fig. 21 comprises a speed estimation part 209, which estimates the travel speed Svi of the mobile telephone station (UE) #m using as input a received uplink signal Sultx , and a timer determination portion 212, which determines using the travel speed Svi as input the duration of the timer for the first timer #m. The adaptive timer control portion 206 produces the travel speed Svi as information of the indicator value Sid.

The adaptive timer control portion 206 of Fig. 22 comprises a variation calculation part 210, which calculates and produces the time variation Stadi in the timing advance (TA) using a timing advance (TA) STa as input , and a timer determination part 213, which determines using the Stadi time variation in the timing advance (TA) as input data the duration of the timer for the first timer #m, and produces the Stadi time variation of the advance of timing (TA) as information of the indicator value Sid.

Fig. 23 is a diagram to explain the procedure for determining and updating the duration of the first and second timers according to the second example embodiment. The adaptive timer control part 206 is assumed to comprise a speed estimation part 209 and a timer determination part 210 (Fig. 21). The timer determination portion 204, 212 determines the duration of the first and second timers, based on the travel speed Svi and the table that predefines the correlations between the travel speed and the duration of the timer.

The base station (Node B) carries out the reception of an uplink signal 1 from the mobile telephone station (UE) #m, the calculation of a timing advance (TA) and the estimation of a travel speed . The base station (Node B) causes the timer determination portion 206 to determine the duration of the first timer #m based on the travel speed and in the table, determine the duration of the first timer #m, and notify the advance of timing (TA) and the speed of travel to the mobile telephone station (UE) #through a downlink signal 1.

Immediately after the transmission of the downlink signal 1 to the mobile telephone station (UE) #m, the base station (Node B) restarts the first timer #m and causes the first timer #m to start operating again.

The mobile telephone station (UE) #m demodulates the downlink signal 1 to reproduce the timing advance (TA) and the travel speed. The mobile telephone station (UE) #m determines the duration of the second timer by means of the timer determination part 204 based on the reproduced travel speed and in the table, updates the duration of the second timer and causes the second timer to start from New to operate. The mobile telephone station (UE) #m then adjusts the transmission timing according to the timing advance (TA) reproduced and transmits an uplink signal 2.

If the same indicator that is used in the first example embodiment is used, the adaptive control process mentioned above using the table is carried out in a manner similar to the first example embodiment.

A possible signal that can be used by the speed estimation part of the base station (Node B) for the estimation of a travel speed is a known signal (Reference signal: RS) for the demodulation of data from the mobile telephone station (UE) transmitted through the uplink shared channel (UL-SCH), and including the uplink signal control information, or an RS for the measurement of CQI that is transmitted to allow the station base (Node B) measure the quality of an uplink line (Channel Quality Indicator: CQI) transmitted through a UL-SCH. Also, a possible signal that can be used to report a travel speed is a signal for data transmission (Physical downlink shared channel: PDSCH) transmitted through a shared downlink channel (DL-SCH).

(Effects of the second example embodiment)

As described above for the second exemplary embodiment, the present invention makes it possible to adaptively control a timer to determine for each mobile telephone station (UE) whether it is in a state considered synchronized or in a state considered synchronized. By this means, you can

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reduce the likelihood that a truly synchronized mobile telephone station will be considered as synchronized. In the case of LTE, it is also possible to reduce the likelihood that a latency before data transmission caused by the need for a truly synchronized mobile telephone station (UE) transmits a synchronized RACH before transmitting a Planning Request.

(Third example embodiment)

Fig. 24 is a block diagram showing the system structure of a wireless communication system according to a third exemplary embodiment of the present invention. In this exemplary embodiment, the calculation of an indicator value to determine the duration of the first and second timers, as well as the determination of the duration of the first and second timers, are carried out by the mobile telephone station.

With reference to Fig. 24, the mobile telephone station (UE) 301 comprises a determination part 103, a signal generating part 104, a transmission information input part 106, a signal transmission part 107, a downlink signal demodulation part 303, an adaptive timer control part 304, a second timer 305 and an uplink signal generation part 306.

At the mobile telephone station (UE #m) 301, the demodulation part of the downlink signal 303 receives from the base station (Node B) 302 a downlink reception signal SoLTx which contains a timing advance (TA ) for a transmission timing, and produces the timing advance (TA) reproduced Miss, which corresponds to the timing advance (TA) received.

The adaptive control part of the timer 304, using as input two or one of the Sm-Ay / timed timing advance (TA) or a downlink reception signal Sdltx, determines the duration of the first timer #m and the second timer as Stui timer update information. It then produces the Stci timer control information, which notifies a second timer reset when the timing advance (TA) played is entered, or when the duration of the second timer has been updated.

The second timer 305 operates in accordance with the Stci timer control information and the STui timer update information, and produces as status information Sg the information of whether the mobile telephone station (UE) #m is in a considered state synchronized or in a state considered out of sync.

When the Sinfo transmission information to be transmitted to the base station (Node B) is entered, the determination part 103 switches the connection according to the status information Ssi. More specifically, it switches the connection to the uplink signal generation part 306 if the information indicates a status considered synchronized, or to the basic signal generation part 104 if the information indicates a state considered to be out of sync.

The basic signal generating part 104 generates and produces a random access signal Sr3, which is necessary to receive a timing advance (TA) from the base station (Node B) for synchronizing an uplink signal.

The uplink signal generation part 306 adjusts the transmission timing according to the timing advance (TA) reproduced SRTa, and generates and produces an uplink signal Sus containing the Sinfo transmission information and the update information Timer Stui-

As the uplink transmission signal Sultx, the signal transmission part 107 transmits the uplink signal Sus if the mobile telephone station is in a considered synchronized state, or the random access signal SR3 if the mobile telephone station is in a state considered out of sync.

Referring to Fig. 24, the base station (Node B) 302 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 307, a timing calculation part 308, a synchronization timer 309 and a downlink transmission part 310.

At the base station (Node B) 302, the determination part 110 switches the connection according to the status information Ssi, which indicates the state of the mobile telephone station (UE) #m. More specifically, it switches the connection to the demodulation part of the uplink signal 307 if the information indicates a status considered synchronized, or to the demodulation part of the basic signal 111 if the information indicates a status considered to be synchronized.

The demodulation part of the basic signal 111 produces as random access detection information Srdi the information indicative of a sequence that exceeds the predefined detection threshold, using as input the received uplink signal Sultx corresponding to the random access signal Srs -

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The demodulation portion of the uplink signal 307 demodulates a received uplink signal Sultx, which corresponds to an uplink information Sus, and produces the reproduced transmitted information Srinfo, which corresponds to the Sinfo transmission information, and the information Srtui reproduced timer update, which corresponds to the timer update information

Stui-

The timing calculation part 308 has a calculation part of TA 3081 and a storage part TA 3082. The timing calculation part 308 uses the calculation part of TA 3081 to detect the reception timing (i.e. a deviation at reception timing) for a received uplink signal Sultx. The timing calculation part 308 calculates a timing advance (TA) Sta, to notify the mobile telephone station (UE) #m based on the detected reception timing, and stores the resulting TA in the TA storage part 3082. It then produces the timing advance (TA), as well as the information that notifies an update of the first timer #m by sending a timing advance (TA) to the mobile telephone station (UE) #m as information of timer control Sjci.

Synchronization timer 309, which has a number M of first timers, operates in accordance with the timer update information reproduced Srtui and with the timer control information Stci, and produces status information SSi if the station information of mobile telephony (UE) #m is in a state considered synchronized or in a state considered synchronized.

The downlink transmission part 310, according to the status information, SSi generates and transmits a downlink transmission signal Sdltx- The downlink transmission signal Sdltx contains a timing advance (TA) STa in the case of a status considered synchronized, or contains a timing advance (TA) Sta and random access detection information Srdi in the case of a status considered as out of sync.

When the duration of the first timer #my and the second timer of the mobile telephone station (UE) #m is determined, the adaptive control part of the timer 304 uses as indicator two or some of a travel speed Svi, which is the result obtained by estimating the travel speed of the mobile telephone station (UE) #m and / or the transmission timing variation information STadi, which is the result obtained by calculating a time variation for the advance of Reproduced timing (TA) SRTa- Fig. 25 shows the structure of the adaptive control part of timer 304 when using as indicators both a travel speed and a time variation in a reproduced timing advance (TA).

The adaptive timer control part 304 of Fig. 25 comprises a speed estimation part 311, which estimates the travel speed Svi of the mobile telephone station (UE) #m using as input data a reception signal of downlink Sdltx; a variation calculation part 312, which calculates and produces the Stadi time variation, in the timing advance (TA) reproduced by using as input of the timing advance (TA) reproduced Miss; and a timer determination part 313, which determines the duration of the first timer #m and the second timer of the mobile telephone station (UE) #m using as input the SVi travel speed and the Stadi time variation in the timing advance (TA) played. The adaptive timer control part comprising any of the speed estimation part 311 or a variation calculation part 312, as well as a timer determination part 313, will be omitted from the description since it is the same as in the first exemplary embodiment described above (see Figs. 3 and 10).

Fig. 26 is a diagram explaining the procedure for determining and updating the duration of a timer according to the third example embodiment. The adaptive control part of the timer 304 is assumed to comprise a speed estimation part and a timer determination part. The timer determination part determines the duration of the timers, based on the travel speed Svi and the table that predefines the correlations between the travel speed and the duration of the timer.

The base station (Node B) receives an uplink signal 1 from the mobile telephone station (UE) #m and calculates a timing advance (TA). Immediately after notifying the timing advance (TA) to the mobile telephone station (UE) #m, the base station (Node B) restarts the first timer #m and causes the first timer #m to start operating again.

The mobile telephone station (UE) #m receives a downlink signal 1 and performs the reproduction of a timing advance (TA) and the estimation of a travel speed. The mobile telephone station (UE) #m determines the duration of the first timer #m and the second timer, based on the estimated travel speed and the table. The mobile telephone station (UE) #m then updates and restarts the second timer and causes the second timer to start operating again. The mobile telephone station (UE) #m adjusts the transmission timing according to the timing advance (TA) reproduced and notifies the duration of the first timer #m by an uplink signal to the base station.

The base station (Node B) receives the uplink signal 2 and reproduces the duration of the first timer #m determined by the mobile telephone station (UE) #m. The base station (Node B) then updates the duration of the first timer #m according to the value played and causes the first timer #m to start operating again.

5 A possible signal that can be used by the speed estimation part of the mobile telephone station (UE) for the estimation of a travel speed is a known signal (Reference signal: RS, which is also called "Pilot channel Common: CPICH ”(Common Pilot CHannel, in English), which is transmitted by means of a shared downlink channel (DL-SCH). Also, a possible uplink signal that can be used to notify the timer duration is a signal for the transmission of 10 data (Physical uplink shared channel: PUSCH) transmitted via a shared uplink channel (UL-SCH).

(Effects of the third example embodiment)

As described above for the third exemplary embodiment, the present invention makes it possible to adaptively control a timer to determine for each mobile telephone station (UE) whether a state considered synchronized or a state considered synchronized is in 15. By this means, the probability that it is decided that a truly synchronized mobile telephone station (UE) is desynchronized can be reduced. In the case of LTE, it is also possible to reduce the likelihood that a latency before data transmission caused by the need for a truly synchronized mobile telephone station (UE) transmits a non-synchronized RACH before transmitting a Planning Request. In the case where the mobile telephone station 20 (UE) determines the duration of the first timer supported by the base station (Node B), as is the case with this example embodiment, a downlink signal from the station base (Node B) may be necessary to indicate a permission to update the duration of the first timer.

(Fourth example embodiment)

Fig. 27 is a block diagram showing the system structure of a wireless communication system 25 according to a fourth embodiment of the invention. In this example embodiment, the calculation of an indicator value to determine the duration of the first timer, as well as the determination of the duration of the first timer, are carried out by the base station, and the calculation of an indicator value for the determination of the duration of the second timer, as well as the determination of the duration of the second timer, they are carried out by the mobile telephone station. It should be noted that the information used for the calculation of an indicator value must be the same between the base station and the mobile telephone station, so that the indicator value calculated by the base station and the calculated indicator value by the mobile phone station they will be identical. In addition, the control information SCi and the reproduced control information Srci described below are conditional information necessary for measurement, rather than indicator values. For example, the information would be a Doppler frequency if a speed of displacement is used as an indicator.

With reference to Fig. 27, the mobile telephone station (UE) 401 comprises a determination part 103, a basic signal generating part 104, a transmission information introduction part 106, a signal transmission part 107 , a downlink signal demodulation part 403, an adaptive timer control part 404, a second timer 405 and an uplink signal generation part 40 406.

At the mobile telephone station (UE #m) 401, the downlink signal demodulation portion 403 receives from the base station (Node B) 402 a downlink reception signal Sdltx, which contains a timing advance ( TA) for a transmission timing, and produces the timing advance (TA) played by Miss, which corresponds to the timing advance (TA) received.

45 The adaptive timer control portion 404, using as input the two or some of the reproduced timing advance (TA) SRiAy / or a downlink reception signal Sdltx, determines the duration of the second timer. It then produces the resulting timer duration as Sjuiu timer update information, as well as the information that notifies a restart of the second timer when the timing advance (TA) played is entered, or when the duration of the second timer 50 is updated as Sjci timer control information. In addition, the adaptive timer control part 404 also produces as information Sci the information used in the calculation of an indicator value to determine the duration of the timer.

The second timer 405 operates according to the timer control information Sjci and the timer update information Sjuiu, and produces as status information Sg the information of whether the mobile telephone station (UE) #m is in a status considered synchronized or in a state considered synchronized.

When the Sinfo transmission information is entered to transmit to the base station (Node B), the determination part 103 switches the connection according to the status information Sg. More specifically,

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Switches the connection to the uplink signal generation part 406 if the information indicates a status considered synchronized, or to the basic signal generation part 104 if the information indicates a status considered to be out of sync.

The basic signal generating part 104 generates and produces a random access signal Srs, which is necessary to receive a timing advance (TA) from the base station (Node B) for synchronization of an uplink signal.

The uplink signal generation part 406 adjusts the transmission timing according to the timing advance (TA) reproduced Miss and generates and produces an uplink signal Sus containing the Sinfo transmission information and the SC control information |

As the uplink transmission signal Sultx, the signal transmission part 107 transmits the uplink signal Sus if the mobile telephone station is in a considered synchronized state, or the random access signal Sr3 if the mobile telephone station is in a state considered out of sync.

Referring to Fig. 27, the base station (Node B) 402 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 407, a timing calculation part 113, an adaptive timer control part 408, a synchronization timer 409 and a downlink transmission part 410.

At the base station (Node B) 402, the determination part 110 switches the connection according to the status information SSi, which indicates the status of the mobile telephone station (UE) #m. More specifically, it switches the connection to the uplink signal demodulation part 407 if the information indicates a status considered synchronized, or to the basic signal demodulation part 111 if the information indicates a state considered to be out of sync.

The basic signal demodulation part 111 produces as random access detection information Srdi the information indicative of a sequence that exceeds the predefined detection threshold, using as input the received uplink signal Sultx corresponding to the random access signal Sr3.

The uplink signal demodulation portion 407 demodulates a received uplink signal Sultx, which corresponds to an uplink signal Sus and produces the reproduced transmission information Srinfo, which corresponds to the Sinfo transmission signal, as well as the information of the reproduced control Srci, which corresponds to the control information Sci.

The timing calculation part 113 detects the reception timing of a received uplink signal Sultx and, based on the reception timing, calculates and produces the timing advance (TA) STa to be notified to the mobile telephone station ( EU) #m.

The adaptive timer control part 408, using as input the two or some of a received uplink signal Sultx and / or a timing advance (TA) STa, determines the duration of the first timer #m. It then produces the duration of the resulting timer as Stuin timer update information, as well as the information that a second timer update notifies by sending a timing advance (TA) to the mobile telephone station (UE) #m as Stci- timer control information

The synchronization timer 409, which has a number M of first timers, operates in accordance with the Stuin timer update information and the Stci timer control information, and produces as status information SSi the information of whether the telephone station mobile (UE) #m is in a state considered synchronized or in a state considered synchronized.

The downlink transmission part 410, according to the status information Ssi, generates and transmits a downlink transmission signal Sdltx. The downlink transmission signal Sdltx contains a timing advance (TA) Sta in the case of a status considered synchronized, or contains a timing advance (TA) Sta and a random access detection information Srdi in the case of a been considered out of sync.

When a timer duration is determined, the adaptive timer control portion 404 (408) uses as indicator two or some of an SVi travel speed, which is the result obtained by determining the travel speed of the station. mobile telephony (UE) #m, and / or Stadi transmission timing variation information, which is the result obtained by calculating a time variation in the timing advance (TA) reproduced SRTa (timing advance (TA ) Ms).

Fig. 28 shows the structure of the adaptive timer control part 404 (408) when both a travel speed and a time variation in a reproduced timing advance (TA) are used as indicators.

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The adaptive timer control part 404 (408) of Fig. 28 comprises a speed estimating part 411 (414), which estimates the travel speed Svi of the mobile telephone station (UE) by use as input of a downlink receiving signal Sdltx (uplink received signal Sultx); a variation calculation part 412 (415), which calculates and produces a variation of Stadi time in the reproduced timing advance (TA) by using as input of the reproduced timing advance (TA) SrTA (timing advance (TA) MS); and a timer determination part 413 (416), which determines the duration of the second timer of the mobile telephone station (UE) #m (first timer #m) using as input the travel speed SVi and the time variation StAdi in the timing advance (TA) played.

The method for determining and updating the duration of the first and second timers according to the fourth exemplary embodiment can be explained by the use of Figs., 11 to 13 above.

The adaptive timer control part 404 (408) is assumed to comprise a variation calculation part 412 (415) and a timer determination part 413 (416) (Fig. 28). The timer determination part determines the duration of the first (second) timer, based on the time variation in the timing advance (TA) reproduced and on the table shown in Fig. 11, which predefines the correlations between the variation of time in the timing advance (TA) and the duration of the timer. In the description of this exemplary embodiment, the method for notifying the amount of deviation in a transmission timing as an absolute value will be considered as a method for notifying the timing advance.

As explained above, each of the timer durations in the table in Fig. 11 has been calculated using the expressions (2) to (4) above, based on different correlations between an amount of timing deviation of transmission during an observation interval and a travel speed at which such an amount of deviation is expected to occur.

In expression (2), DTA [ps] is the deviation value in the transmission timing; v [km / h] is the travel speed of the mobile telephone station (UE); t [s] is the time that causes a deviation of DtA; and 6.7 [ps / km] is a Round Trip Delay (RTD), which is a propagation delay caused between the base station (Node B) and the mobile telephone station (UE). In expression (3), Ad [ps] is the amount of deviation in the transmission timing caused in a period of At [s].

In this exemplary embodiment, a case will be considered in which the mobile telephone station (UE) has successfully demodulated a downlink reception signal, and in which the value of the timing advance (TA) reproduced coincides with the timing advance value (TA) calculated by the base station (Node B).

Assume that the variation calculation part of the base station (Node B) calculates a time variation in a timing advance (TA) at regular time intervals, that is, by 10 [s], for a telephone station mobile (UE) # 1 and whose results are those shown in Fig. 12. At each of the times (to, ti, t2, faith), the timer determination part determines the duration of the first and second timers and adaptively control these timers. It is assumed herein that the initial value Ttmo for the first and second timers is 1.5 [s] as described above, which is the duration of time determined for a travel speed of 350 [km / h].

The time variation in the timing advance (TA) of a mobile telephone station (UE) # 1 in to calculated by the variation calculation part of the base station (Node B) is 2.18 [ps / 10 s]. With reference to the table in Fig. 11, the variation is between 0.56 [ps / 10 s] and 2.23 [ps / 10 s], so that the duration of the timer can exceed the initial value of 1, 5 [s]. Based on the table, the duration of the first timer # 1 is determined to be 4.5 [s] and the duration of the first timer # 1 is updated.

Immediately after the information of the timing advance (TA) to the mobile telephone station (UE) # 1, the base station (Node B) restarts the first timer # 1 and causes the first timer # 1 to start operating again .

On the other hand, at time t0 + t (where t is a process latency from when the base station (Node B) calculates a time variation in a timing advance (TA) until the mobile telephone station (UE ) # 1 calculates a time variation in the timing advance (TA) reproduced), the value of the time variation in the timing advance (TA) being reproduced resulting from the calculation by the mobile telephone station (UE) # 1 also of 2.18 [ps / 10 s]. Therefore, the duration of the second timer is determined to be 4.5 [s], based on the table in Fig. 11. The mobile telephone station (UE) # 1 then updates and restarts the second timer and causes The second timer starts operating again.

Similarly, the time variations in the timing advance (TA) in t = ti, t2, are calculated by the base station (Node B) and the time variations in the timing advance (TA) reproduced in t = ti + r, t2 + T, Í3 + T calculated by the mobile telephone station (UE) #m are 1.45 [ps / 10 s], 1.92 [ps / 10 s] and 3.28 [ ps / 10 s]. With reference to the table in Fig. 11, it can be determined that the durations of the first timer # 1 and the second timer of the mobile telephone station (UE) # 1 are 4.5 [s], 4.5 [s ] and 1.5 [s], respectively.

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Fig. 13 shows the results of the determination of the first and second temponzadores as described above.

Fig. 29 is a diagram explaining the procedure for determining and updating the duration of a timer according to the fourth example embodiment.

The base station (Node B) receives an uplink signal 1 from the mobile telephone station (UE) #m, calculates a timing advance (TA) and then calculates a time variation in the timing advance (TA) . The base station (Node B) determines and updates the duration of the first timer #m, based on the time variation calculated in the timing advance (TA) and in the predefined table. Immediately after notifying the timing advance (TA) to the mobile telephone station (UE) #m in a downlink signal 1, the base station (Node B) resets the first timer #my and makes the first timer #m Start operating again.

The mobile telephone station (UE) #m receives and demodulates the downlink signal 1 to reproduce the timing advance (TA). The mobile telephony station (UE) #m then calculates a variation in time in the reproduced timing advance (TA), and determines the duration of the second timer, based on the same predefined table as that used by the base station ( Node B). Immediately after updating the duration of the second timer, the mobile telephone station (UE) #m restarts the second timer and causes the second timer to start operating again. If the mobile telephone station (UE) #m is rotating around the base station (Node B) while traveling, it is desirable to determine a longer duration using only a variation (time variation) as an indicator.

On the other hand, if the travel speed is used as an indicator to determine a timer duration in this example embodiment, one possible method that can be used is that one of the base station (Node B) or the mobile telephone station ( UE) Estimate a Doppler frequency of a known signal and notify the result of the estimate to the other party.

As described above for the fourth exemplary embodiment, the present invention makes it possible to adaptively control a timer to determine for each mobile telephone station (UE) whether it is in a condition considered synchronized or in a synchronized state.

(Effects of the fourth example embodiment)

In accordance with this exemplary embodiment, by using the method described above it is possible to reduce the probability that it is decided that a truly synchronized mobile telephone station is out of sync, because the duration of the timer can be adaptively controlled for each station of mobile telephony In the case of LTE, it is also possible to reduce the probability that a latency, before the data transmission caused by the need for a truly synchronized mobile telephone station (UE), to transmit a non-synchronized RACH before transmitting a Request of planning.

Although, in the exemplary embodiments of the present invention described above, the duration of the timer used to determine whether the mobile telephone station (UE) is in a state considered synchronized or in a state considered synchronized based on its travel speed or a variation of time in a timing advance (TA) for a transmission timing, it is also possible to determine the duration of the timer taking into account the services carried out by each mobile telephone station (UE). This is because the reading time varies depending on what service is being performed. In this case, a longer timer duration can be set for a longer reading time. It should be noted, however, that a longer timer duration leads to a greater possibility that a mobile telephone station will be out of sync before expiration. To prevent this problem from occurring, it is necessary to establish and configure an appropriate timer duration that is considered within an acceptable tolerance.

In addition, the position information of the GPS or other similar sources can also be used as a means to estimate a travel speed.

(Fifth example embodiment).

Fig. 30 is a block diagram showing the system structure of a wireless communication system according to a fifth embodiment of the present invention.

With reference to Fig. 30, the mobile telephone station (UE) 501 comprises a determination part 103, a basic signal generating part 104, a transmission information input part 106, a signal transmission part 107 , a downlink signal demodulation part 503, an adaptive timer control part 504, a second timer 505 and an uplink signal generation part 506.

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Also with reference to Fig. 30, the base station (Node B) 502 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 507, a calculation part of timing 508, a timer demodulation part 509, a synchronization timer 510 and a downlink transmission part 511.

In this exemplary embodiment, the mobile telephone station (UE) #m calculates the value of an indicator based on which to estimate a desynchronized period, determines the duration of the second timer so that it is inversely proportional to the value of the indicator, updates the timer duration so determined and notifies the value of the indicator to the base station (Node B). The base station (Node B), on the other hand, determines the duration of the first timer #m so that it is inversely proportional to the value of the reproduced indicator, and updates the duration of the timer thus determined.

(Sixth example embodiment)

Fig. 31 is a block diagram showing the system structure of a wireless communication system according to a sixth embodiment of the present invention.

With reference to Fig. 31, the mobile telephone station (UE) 601 comprises a determination part 103, a basic signal generating part 104, a transmission information input part 106, a signal transmission part 107 , a downlink signal demodulation part 603, an adaptive timer control part 604, a second timer 605 and an uplink signal generation part 606. The value calculation part of the indicator 604 comprises at least some of the speed estimation part 344 and the variation calculation part 312 shown in Fig. 25.

Also with reference to Fig. 31, the base station (Node B) 602 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 607, a calculation part of timing 608, a timer determination part 609, a synchronization timer 610 and a downlink transmission part 611.

In this exemplary embodiment, the mobile telephone station (UE) #m calculates the value of an indicator based on which to estimate a synchronized period, and reports the indicator value thus calculated to the base station (Node B). In turn, the base station (Node B) determines the duration of both the first timer #m and the second timer of the mobile telephone station (UE) #m, so that it is inversely proportional to the indicator value reproduced, it updates the duration of the first timer # 1 and notifies the duration of the second timer to the mobile telephone station (UE) #m. The mobile telephone station (UE) #m then reproduces the duration of the second timer determined by the base station (Node B) and updates the duration of the second timer accordingly.

(Seventh example embodiment)

Fig. 32 is a block diagram showing the system structure of a wireless communication system according to a seventh embodiment of the present invention.

With reference to Fig. 32, the mobile telephone station (UE) 701 comprises a determination part 103, a basic signal generating part 104, a transmission information input part 106, a signal transmission part 107 , a downlink signal demodulation part 703, a timer determination part 704, a second timer 705 and an uplink signal generation part 706.

Also with reference to Fig. 32, the base station (Node B) 702 comprises a determination part 110, a basic signal demodulation part 111, an uplink signal demodulation part 707, a calculation part of timing 708, a calculation part of the indicator value 709, a synchronization timer 710 and a downlink transmission part 711. The calculation part of the indicator value 704 comprises at least some of the speed estimation part 118 and the variation calculation part 119 shown in Figs. 3, 10 and 14.

In this exemplary embodiment, the base station (Node B) calculates the value of an indicator based on which to estimate a synchronized period, and notifies the indicator value thus calculated to the mobile telephone station (UE) #m. In turn, the mobile telephone station (UE) #m determines the duration of both the first timer #m and the second timer so that it is inversely proportional to the indicator value played, updates the duration of the second timer and reports the duration of the second timer. First timer #m to the base station (Node B). The base station (Node B) then reproduces the duration of the first timer #m determined by mobile telephone station (UE) #m and updates the duration of the first timer #m correspondingly.

With reference to Fig. 32, the mobile telephone station (UE) 701 comprises a determination part 103, a basic signal generating part 104, a transmission information input part 106, a signal transmission part 107 , a downlink signal demodulation part 703, a control part

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adaptive timer 704, a second timer 705 and an uplink signal generation portion 706.

(Eighth example embodiment)

Fig. 33 is a block diagram illustrating a schematic concept of a wireless communication system according to an eighth embodiment of the present invention. The mobile telephone station (UE) 801 and the base station (Node B) of the present invention have one of the structures of the example embodiments described above. The present invention is applied in such a way that, when the mobile telephone station (UE) 801 moves from the communication coverage 8021a of the base station (Node B) 802a to the communication coverage 8021b of the base station ( Node B) 802b, (1) the mobile telephone station (UE) 801 receives a notification from the base station (Node B) 802b; (2) in response to such information, the mobile telephone station (UE) 801 notifies the last timer duration determined within the communication coverage 8021a, based on one of the structures of the example embodiments described above; and (3) the base station 802b in turn notifies the value of the timer duration setting to the mobile telephone station 801, using one of the methods described with respect to the example embodiments described above.

According to this exemplary embodiment, even when a mobile telephone station (UE) leaves the communication coverage of one base station (Node B) towards another, it is possible to carry out a control of a timer that is adaptive for each station mobile telephony (UE), to determine if the mobile telephony station is in a state considered synchronized or in a state considered synchronized between the mobile telephony station (UE) and such another base station (Node B).

(Ninth example embodiment)

Fig. 34 is a block diagram illustrating a schematic concept of a wireless communication system according to a ninth embodiment of the present invention. The mobile telephone station (UE) and the base station (Node B) of the present invention have one of the structures of the example embodiments described above. The present invention is applied in such a way that, when the mobile telephone station (UE) 801 moves from the communication coverage 8021a of the base station (Node B) 802a to the communication coverage 8021b of the base station ( Node B) 802b, (1) the mobile telephone station (UE) 801 responds in the manner described with respect to the example embodiments described above; (2) the base station (Node B) 802b requests from the base station (Node B) 802a information related to the mobile telephone station (UE) 801, using one of the methods described with respect to the described example embodiments previously; (3) in response to this request, the base station (Node B) 802a notifies the information relating to the mobile telephone station (UE) 801 to the base station (Node B) 802b; and (4) based on the information notified from the base station (Node B) 802a, the base station 802b notifies the timer duration setting value to the mobile telephone station 801. More specifically, if produces a transfer from a mobile telephone station to another base station, the last synchronization duration that is being used by the original base station is transferred from the original base station to another such base station, to which The mobile phone station is transferred.

According to this exemplary embodiment, even when a mobile telephone station (UE) leaves the communication coverage of one base station (Node B) towards another, it is possible between different base stations (Node B) to reduce signaling and carry out a control of a timer that is adaptively for each mobile telephone station (UE) to determine whether the mobile telephone station is in a state considered synchronized or in a state considered synchronized, because the information relating to the Mobile telephone station (UE) has been transmitted between the current (new) base stations (Node B).

(Tenth example embodiment)

Fig. 35 is a block diagram showing the schematic concept of a wireless communication system according to a tenth embodiment of the present invention. The mobile telephone station (UE) and the base station (Node B) of this example embodiment have one of the structures of the example embodiments described above. The present invention is applied in such a way that, when the mobile telephone station (UE) 801 moves from the communication coverage 8021a of the base station (Node B) 802a to the communication coverage 8021b of the base station ( Node B) 802b, (1) the base station 802a notifies the base station 802b of the last timer duration of the mobile telephone station 801, in addition to the information necessary for a transfer; (2) the mobile telephone station 801 notifies the base station 802b that it has received a transfer from the base station 802a; and (3) the base station 802a notifies the mobile telephone station 801 of the last value of the timer duration reported from the base station 802a. More specifically, if a transfer from a mobile telephone station to another base station occurs, the last timer duration that is being used by the original base station is transferred from the original base station to another station. base to which transfers are made from the mobile phone station.

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According to this exemplary embodiment, even when a mobile telephone station (UE) leaves the communication coverage of one base station (Node B) towards another, it is possible between different base stations (Node B) to reduce signaling and carry out a control of a timer that is adapted for each mobile telephone station (UE) to determine if the mobile telephone station is in a state considered synchronized or in a state considered synchronized, because the information related to The mobile telephone station (UE) has been transmitted between the current (new) base stations (Node B).

(First example)

An example of the present invention will now be described.

A TA is a signal obtained by time synchronization detection, and is sent from a base station to a mobile telephone station. The mobile telephone station corrects a propagation delay and adjusts a transmission timer using the TA, so that a timing deviation of the uplink signals sent from other mobile telephone stations will be found in the receiver window. A time division multiplexing of an uplink is performed using a TA to prevent overlapping transmissions through the uplinks of a plurality of mobile telephone stations.

Timing control is necessary when:

(1) a mobile telephone station accesses a cell for the first time, which includes an initial access and a transition from a state of suspension to an active one;

(2) a mobile telephone station accesses a cell after a long-term DTX; or

(3) the base station considers that a TA must be transmitted, a situation that may occur, for example, during data transmission.

If a cell (in particular a cell with a small radius) in which an uplink signal overlap is not expected to occur during the maximum propagation delay, timing control for the uplinks may not be necessary.

TA commands can have different control accuracy, as described below.

(1) a one-bit TA command, which has low reliability but is frequently transmitted; or

(2) a multi-bit TA command, which has high reliability but is transmitted infrequently.

A mobile telephone station does not know the actual synchronization timing in a base station. A base station, on the other hand, can recognize whether or not a mobile telephone station is actually synchronized, from the reference signal of an uplink, the data signal or the control signal.

A mobile telephone station can be in one of two states, which can be decided by using a TA (TA status):

(1) synchronized state; or

(2) desynchronized state.

The mobile phone station determines its TA status according to the following rules:

(1) a mobile telephone station enters a synchronized state when it receives a single or multi-bit TA command, causing a timer called T_SYNC to start operating again; Y

(2) A mobile telephone station enters a synchronized state when the T_SYNC timer expires.

The T_SYNC timer value is notified from a base station to a mobile phone station after the establishment or restoration of an RRC.

T_SYNC is controlled for each mobile telephone station and optimized according to the state of the specific channel for each mobile telephone station. For example, a base station may set a small value as the Initial value of T_SYNC and later change it to a higher value with respect to a mobile telephone station if it takes the mobile telephone station much longer than others before entering In a desynchronized state.

A control of T_SYNC can be maintained through a transfer to another cell. When a transfer between different base stations occurs, the same value of T_SYNC can be set before and after the transfer between these base stations, using any of the following procedures: the mobile telephone station notifies the duration of its timer to the target base station where they are received

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transfers from the mobile telephone station, and the source base station transfers the last duration of the timer being used within the source cell to the target base station. When a mobile telephone station moves from one cell to another of the same base station, the base station can set the same value of T_SYNC before and after a transfer.

The first to ninth example embodiments can be applied to such a T_SYNC control.

In order to resolve the issues described above, there is a wireless communication system such as the one described below.

In a wireless communication system provided by the present invention,

A base station (Node B) contains a first timer to decide whether a mobile telephone station (UE) is in a state considered synchronized or in a state considered synchronized, one for each of the M mobile telephone stations (UE) (in which M is a natural number), that is, M first timers in total;

with respect to the uplink signals of the mobile telephone station (UE) of order m (in which m is an integer between 1 and M) #m, the base station (Node B) calculates a timing advance ( TA) (Timer advance: TA) of a transmission timing, which is necessary for the uplink signals of M mobile telephone stations (UE) to synchronize with each other at the base station (Node B) and, immediately after the notification of the timing advance (TA) to the mobile telephone station (UE) #m, makes the first timer #m decide whether the mobile telephone station (UE) #m is in a state considered synchronized or in a state considered out of sync to operate;

immediately after being notified of the timing advance (TA), the mobile telephony station (UE) #m causes the second timer used to decide its own operating status to set a transmission timing according to the advance of timing (TA), modify the format of an uplink signal according to its own state and transmit the resulting uplink signal; Y

the two or some of the base station (Node B) and / or the mobile telephone station (UE) #m determine and adaptively update the duration of the two or some of the first timer #m and / or the second timer according with the value of an indicator based on which to estimate a synchronized period in which the mobile telephone station (UE) #m in a considered synchronized state passes to a considered considered synchronized state.

The structure of the wireless communication system according to each of the example embodiments will be summarized below.

The first Wireless communication system has a structure in which the base station (Node B) calculates the value of an indicator based on which to estimate a synchronized period, determines the duration of both the first timer #m and the second timer of the mobile telephone station (UE) #m so that it is inversely proportional to the Indicator value, updates the duration of the first timer #m and notifies the duration of the second timer thus determined to the mobile telephone station (UE) #m; and the mobile telephone station (UE) #m reproduces the duration of the second timer determined by the base station (Node B), and updates the duration of the second timer accordingly.

The second Wireless communication system has a structure in which the base station (Node B) calculates the value of an indicator based on which to estimate a synchronized period, determines the duration of the first timer #m so that it is inversely proportional to the Indicator value, updates the duration of the first timer #m and notifies the value of the indicator to the mobile telephone station (UE) #m; and the mobile telephone station (UE) #m determines the duration of the second timer so that it is inversely proportional to the indicator value reproduced, and updates the duration of the second timer.

The third Wireless communication system has a structure in which the mobile telephone station (UE) #m calculates the value of an indicator based on which to estimate a synchronized period, determines the duration of both the first timer #m and the second timer so that they are inversely proportional to the value of the indicator, it updates the length of the second timer and notifies the duration of the first timer #m so determined to the base station (Node B); and the base station (Node B) reproduces the duration of the first timer #m determined by the mobile telephone station (UE) #m and updates the duration of the first timer #m correspondingly.

The fourth Wireless communication system has a structure in which the mobile telephone station (UE) calculates the value of an indicator based on which to estimate a synchronized period, determines and updates the duration of the second timer so that it is inversely proportional to the value of the indicator, and notifies the value of the indicator to the base station (Node B); and the base station (Node B) determines and updates the duration of the first timer #m so that it is inversely proportional to the indicator value played.

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The fifth wireless communication system has a structure in which the base station (Node B) and the mobile telephone station (UE) #m individually calculate the value of an indicator based on which to estimate a synchronized period, and determine and individually update the duration of the first timer #m and the second timer so that they are inversely proportional to the value of the indicator.

The sixth Wireless communication system has a structure in which the mobile telephone station (UE) #m calculates the value of an indicator based on which to estimate a synchronized period and reports the value to the base station (Node B); the base station (Node B) determines the duration of both the first timer #m and the second timer of the mobile telephone station (UE) #m, so that it is inversely proportional to the indicator value reproduced, updates the duration of the first #m timer notifies the duration of the second timer to the mobile telephone station (UE) #m; and the mobile telephone station (UE) #m reproduces the duration of the second timer determined by the base station (Node B) and updates the duration of the second timer accordingly.

The seventh Wireless communication system has a structure in which the base station (Node B) calculates the value of an indicator based on which to estimate a synchronized period, and notifies the indicator value to the mobile telephone station (UE) #m; The mobile telephone station (UE) #m determines the duration of both the first timer #m and the second timer so that they are inversely proportional to the value of the indicator played, updates the duration of the second timer, and notifies the duration of the first timer # ma mobile phone station (UE) #m; and the base station (Node B) reproduces the duration of the first timer #m determined by the mobile telephone station (UE) #m and updates the duration of the first timer #m correspondingly.

As an indicator based on which to estimate a synchronized period, for use in each wireless communication system provided by the present invention, both or some of the travel speed of a mobile telephone station (UE) and / or a time variation in a timing advance (TA), for example.

An example of a method to determine the duration of the first and second timers according to the value of an indicator is to first prepare a table that predefines the correlations between the Indicator and the duration of the timer and then determine the duration of the timer based on the value of calculated indicator and in the table.

As explained above, by means of the adaptive control of the duration of a timer used to decide whether a mobile telephone station is in a state considered synchronized or in a state considered synchronized for each mobile telephone station with respect to speed of travel, the probability that a latency before data transmission increases when it is decided that the mobile telephony station that is actually synchronized is considered to be synchronized can be reduced.

Although the present invention has been described by taking as examples several preferred exemplary embodiments, it will be apparent that the invention is not limited to these exemplary embodiments, but can be performed with a variety of modifications without departing from the spirit and scope of its technical principle. .

Claims (5)

5 10 fifteen twenty 25 30 35 40 1. A base station (102) for communicating with at least one of the mobile telephone stations (101), the base station (102) comprising: a timer unit (115) that establishes a period to decide whether an uplink signal from a mobile telephone station (101) is synchronized; Y a timer control unit (114) that is capable of determining the specific period for each of the mobile telephone stations (101) and notifying the period to the mobile telephone station (101) after the establishment or restoration of a RRC 2. A mobile telephone station (101) for communicating with a base station (102) connected to other mobile telephone stations, the mobile telephone station (101) comprising: a control unit (103) that decides whether an uplink signal to the base station (102) is synchronized based on a period sent from the base station (102) that is able to determine the specific period for each of mobile phone stations (101), in which the mobile telephone station (101) receives the period after the establishment or restoration of an RRC. 3. A control method of a base station (102) for communicating with at least one of the mobile telephone stations (101), the method comprising: establish a period to decide whether an uplink signal from one of the mobile telephone stations (101) is synchronized, in which the period is specific to each of the mobile telephone stations (101); Y send the period to the mobile telephone station (101) after the establishment or restoration of an RRC. 4. A control method of a mobile telephone station (101) for communicating with a base station (102) connected to other mobile telephone stations, the method comprising: deciding whether an uplink signal to the base station (102) is synchronized based on a period sent from the base station (102) that is capable of determining the specific period for each of the mobile telephone stations (101) ; receive the period from the base station after the establishment or restoration of an RRC. 5. A wireless communication system that includes a base station (102) for communicating with at least one of the mobile telephone stations (101), in which the base station (102) comprises: a timer unit (115) that establishes a period to decide whether an uplink signal from the mobile telephone station (101) is synchronized; a timer control unit (114) that is capable of determining the specific period for each of the mobile telephone stations (101); Y wherein the mobile telephone station (101) comprises: a unit that decides whether an uplink signal to the base station is synchronized based on the period sent from the base station (102) that is able to determine the specific period for each of the mobile telephone stations (101) , in which the mobile telephone station (101) receives the period of the base station (102) after the establishment or restoration of an RRC.